Right atrial pressure, not Doppler jet velocity, is the problem in estimating pulmonary pressure when tricuspid regurgitation is severe

Echocardiography allows estimation of right ventricular (RV) systolic pressure by adding the estimated right atrial pressure (RAP) to the systolic pressure gradient between the RV and right atrium (RA) calculated from the tricuspid regurgitant (TR) Doppler velocity. RV systolic pressure is equivalent to pulmonary artery systolic pressure (PASP) in the absence of pulmonic valve stenosis. Some degree of TR is present in about 80% of patients undergoing echocardiography, often only a trace or mild amount but just enough to allow PASP estimation which is now a standard echocardiographic reporting element. Non-invasive estimates of PASP initially were validated in the 1980s,1 2 with demonstration of a close correlation between simultaneous invasive and non-invasive PASP measurements. Non-invasive PASP estimates are used widely to adjust medical therapy, determine the timing of interventions and provide prognostic information in patients with a range of cardiovascular conditions. © Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.